Burning Man is an art festival that takes place on a dried lake bed in the desert at altitude in Nevada, USA. 30-50,000 people create a city, Black Rock City, for one week, and brave the elements (30-45 Celsius, 0% humidity)and each other. I is not a party per say but you can party your arse off 24-7 if you so desire as there are many many many sound systems, some that are simply massive. There's also vast amounts of installation and interactive art, it's really a photographers wet dream.
I condensed a huge pile of photos from our trip last summer and put them online if anyone is interested:
[URL]http://www.area709.com/darvin/gallery/view/72/[/URL]
Enjoy! :D